Lawrence Doniach Research Articles

Vortex phase diagram and transition in (Bi1.6Pb0.4Sr2Ca2Cu3O10-δ)1-x(SnO2)x superconductors

The superconducting vortex phase diagram of (Bi1.6Pb0.4Sr2Ca2Cu3O10-δ)1-x(SnO2)x ceramics, where x = 0, 0.002, 0.004, 0.006, 0.008, and 0.010, was investigated using resistivity measurement under magnetic fields. If the value of the offset critical temperature (Tc,offset) monotonously decreased on the SnO2-added samples, then the mean-field critical temperature (Tmf) would slightly improve on the x = 0.002 sample. The excess conductivity of all samples was analyzed based on the Aslamazov–Larkin and Lawrence–Doniach models. The c-axis coherence length at 0 K (ξc(0)) and the interlayer coupling strength were optimized on the x = 0.002 sample. The activation energy (U0) calculated using the Arrhenius model was also increased, and the maximum for the x = 0.002 sample was reached. The upper critical field (Bc2) deduced using the Werthamer–Helfand–Hohenberg model was also enhanced for the x = 0.002 sample. The small bundle field (Bsb), large bundle field (Blb), irreversibility field (Birr), and Bc2 were combined for the vortex phase (B-T) diagram of the x = 0.000 and x = 0.002 samples. All pinning regimes of the x = 0.002 sample were extended, clearly revealing the improvements in the flux pinning properties in that sample.

The effect of medium doses electron irradiation on the scattering of charge carriers in YBa2Cu3O7-δ single crystal

The influence of electron irradiation with energies of 0.5–2.5 MeV with fluences up to 70 × 1018 cm–2 on the electrical resistivity in the basal plane of YBa2Cu3O7–δ single crystals in the temperature range from the superconducting transition, Tc, to 300 K has been studied. Such irradiation leads to the appearance of a significant number of defects that cause a decrease in anisotropy, an appreciable increase in phonon scattering, reduction of Tc, and broadening of the superconducting transition. Under the conditions specified, the temperature dependence of electrical resistivity is approximated with high accuracy by the charge carriers’ scattering on defects and phonons, and fluctuating conductivity in the Lawrence-Doniach (LD) model. The dependences of approximation parameters on fluence are discussed.

Excess Conductivity Analysis of an YBCO Foam Strut and Its Microstructure.

Struts of a superconducting YBa2Cu3Oy (YBCO) foam prepared by the infiltration growth method on the base of commercial polyurethane foams were extracted from the bulk, and thoroughly characterized concerning the microstructure and the magnetoresistance, measured by the four-point technique. Optical microscopy, electron microscopy, electron backscatter diffraction and atomic force microscopy observations indicate a unique microstructure of the foam struts which shows a large amount of tiny Y2BaCuO5 (Y-211) particles (with diameters between 50 and 100 nm) being enclosed in channel-like grain boundaries between the YBCO grains and a one-of-a-kind surface of the struts covered with Ba3Cu5Oy-particles. The resistance data obtained at temperatures in the range 4.2 K ≤T≤ 150 K (applied magnetic fields ranging from 0 to 7 T) were analyzed in the framework of the fluctuation-induced conductivity (FIC) approach using the models of Aslamazov-Larkin (AL) and Lawrence-Doniach (LD). The resulting FIC curves reveal the presence of five distinct fluctuation regimes, namely, the short-wave (SWF), one-dimensional (1D), two-dimensional (2D), three-dimensional (3D), and critical (CR) fluctuation domains. The analysis of the FIC data enable the coherence length in the direction of the c-axis at zero-temperature (ξc(0)), the irreversibility field (Birr), the upper critical magnetic field (Bc2), the critical current density at T= 0 K (Jc(0)) and several other parameters describing the the material's superconducting properties to be determined. The present data reveal that the minuscule Y-211 particles found along the YBCO grain boundaries alter the excess conductivity and the fluctuation behavior as compared to conventional YBCO samples, leading to a quite high value for Jc(0) for a sample with a non-optimized pinning landscape.

Generalization of interlayer tunneling models to cuprate superconductors with charge density waves

At the beginning of cuprate superconductors, the interlayer tunneling (ILT) and Lawrence-Doniach (L-D) models, which connect the CuO planes by Josephson coupling were considered the leading theoretical proposals for these materials. However, measurements of the interlayer magnetic penetration depth $\lambda_{c}$ yielded larger values than required by the ILT model. After the discovery of planar stripes and incommensurate charge ordering, it was also possible to consider Josephson coupling between these mesoscopic charge domains or blocks. We show that the average intralayer is larger than the interlayer coupling and comparable with the condensation energy, leading to a superconducting transition by long-range phase order. Another consequence is that the ratio $[\lambda_{c}/\lambda_{ab}]^2$ is directly proportional resistivity ratio $\rho_c/ \rho_{ab}$ near the superconducting transition temperature in agreement with several measurements.

Impact of adding bismuth vanadate (BiVO4) nanoparticles on the electrical and mechanical properties of Cu0.5Tl0.5Ba2Ca2Cu3O10-δ ceramic

A mechanochemical route was used to prepare bismuth vanadate (BiVO4) with an average grain size of 20 nm. To obtain (BiVO4)x/Cu0.5Tl0.5Ba2Ca2Cu3O10-δ composites, appropriate amounts of BiVO4 (x) were added to Cu0.5Tl0.5Ba2Ca2Cu3O10-δ via a solid-state reaction. The superconducting critical temperature (Tc) was dropped from 119.5 to 103.5 K with x. The different conduction mechanisms were studied using the Aslamazov–Larkin and Lawrence–Doniach models. Four different fluctuation zones were observed. As the BiVO4 content rose the coherence length was increased from 19.69 to 39.30 Å. Superconducting parameters such as thermodynamic critical field Bc(0), lower critical magnetic field Bc1(0), upper critical magnetic field Bc2(0), and critical current density Jc(0) were decreased with x. Furthermore, the mechanical strength was studied through Vickers microindentation test and variety of mechanical parameters, including elastic modulus (E), yield strength (Y), fracture toughness (K), and brittleness index (B), were determined as a function of BiVO4 content.Graphical abstract

YBCO polycrystal co-added with BaTiO3 and WO3 nanoparticles: Fluctuation induced conductivity and pseudogap studies

We report the effect of the addition of BaTiO3 and WO3 nanoparticles on the pseudogap and excess conductivity of YBCO polycrystal. The excess conductivity analysis showed that the experimental data of pure and sample added with low amount of WO3 and BaTiO3 were perfectly described by the 2D Maki-Thompson (MT) and 3D Aslamazov-Larkin (AL) models. A sharp decrease in excess conductivity was obtained for samples added with high amount of nanoparticles where the analysis indicated the presence of the AL contribution and Lawrence-Doniach (LD) models. The pseudogap (PG) results showed that the value of Tpair (the temperature at which local pairs are transformed from strongly bound bosons into the fluctuating Cooper pairs) increased from around 117 K for the pure sample to around 187 K for sample co-added with low amount of nanoparticles. The pseudogap Δ*(TG) reduced from 230.9 K (for pure sample) to 223.4 K (for added sample).

Correlation between local structure variations and critical temperature of (Bi1.6Pb0.4Sr2Ca2Cu3O10+δ)1-x(TiO2)x superconductor

TiO2 doping content affects the critical temperature (Tc) and the variations of local structure on Bi1.6Pb0.4Sr2Ca2Cu3O10+δ. The (Bi1.6Pb0.4Sr2Ca2Cu3O10+δ)1-x(TiO2)x samples were fabricated with the solid-state reaction process, where x = 0, 0.002, 0.004, 0.006, 0.008, and 0.01. The Tc values of the samples were obtained by measuring resistivity versus temperature, indicating that Tc gradually decreased with increasing doping content (x). To explain the obtained degradation of Tc, carrier properties, role of interlayer coupling, and local structure were systematically investigated using Azlamozov–Larkin theory and its Lawrence–Doniach modification for strong anisotropic superconductors. The calculation of excess conductivity at the mean field region showed that the c-axis coherence length (ξc) and the effective inter-layering spacing (d) increased with increasing doping content. X-ray diffraction patterns also showed that the bond distances increased with increasing TiO2 content. The copper valence (V) and carrier concentration (p) of the samples were determined by analyzing the Cu L2,3-edge X-ray absorption near edge structure spectra. The values of V and p showed the same trend of decreasing with increasing x. A close correlation between the changes in local structure parameters and degradation of Tc of (Bi1.6Pb0.4Sr2Ca2Cu3O10+δ)1-x(TiO2)x was then probably concluded.

Infrared Spectroscopy and Excess Conductivity Analysis for (Y3Fe5O12)x/Cu0.5Tl0.5Ba2Ca2Cu3O10-δ Composites

In this study, the influence of adding Yttrium iron garnet (Y3Fe5O12) nanoparticles (NPs) on the microstructure and fluctuation-induced conductivity (FIC) of Cu0.5Tl0.5Ba2Ca2Cu3O10-δ (CuTl-1223) superconductor was studied. Y3Fe5O12 NPs were produced by the co-precipitation technique. By solid state route, (Y3Fe5O12)x/Cu0.5Tl0.5Ba2Ca2Cu3O10-δ composites, with x = 0.00, 0.02, 0.04, 0.06, 0.08, and 0.10 wt. % were prepared. The tetragonal unit cell parameters of (Y3Fe5O12)x/Cu0.5Tl0.5Ba2Ca2Cu3O10-δ composites were found to be invariable with Y3Fe5O12 content. The volume fraction of the host phase was increased with Y3Fe5O12 addition till x = 0.04 wt. %. The different vibrational modes of the samples were identified through Fourier transform infrared spectroscopy (FTIR). The transition from normal to the superconducting state, for the prepared composites, was done through d.c resistivity measurements from room temperature down to zero critical temperature (T0). The Aslamazov–Larkin (AL) model was used to examine fluctuation regions in resistivity-temperature curves. At high temperatures, short wave fluctuation was observed. A cross-over between short wave fluctuation and the mean-field region was spotted at lower temperatures. The mean field region for the examined composites was composed of two-dimensional fluctuations along with one-dimensional fluctuation. The coherence length along the c-axis ζc(0), interlayer coupling (J), and anisotropy parameter (γ) were estimated from the Lawrence–Doniach (LD) model as a function of Y3Fe5O12 content.

Annealing Effects on FluctuationInduced Conductivity of (Cu0.5Tl0.25Hg0.25)Ba2Ca3Cu4O12-δ, Superconductor

In the light of the Aslamazov–Larkin theory of fluctuation-induced conductivity (FIC), the excess conductivities of as-prepared, nitrogen-post-annealed, oxygen-post-annealed, and air-post-annealed samples of (Cu0.5Tl0.25Hg0.25)Ba2Ca3Cu4O12–δ have been determined. It is observed from FIC measurements that the crossover of a three-dimensional (3D) to a two-dimensional (2D) behavior of fluctuations is shifted to higher temperatures by the post-annealing of samples in nitrogen, oxygen, and air. We have accredited this behavior to an increase in the grain size and the improved carrier concentration in the conducting CuO2 planes. In addition, it is also noted that, after the post-annealing of samples in nitrogen, oxygen, and air, the width of the three-dimensional region of fluctuations is also enlarged. Furthermore, two distinct parameters (coherence length and interplanar coupling) are also estimated by the Lawrence–Doniach equations and found to be increased by the post annealing in nitrogen, oxygen, and air.

Excess Conductivity Analyses in Bi-Pb-Sr-Ca-Cu-O Systems Sintered at Different Temperatures

This paper studies the effects of the sintering temperature on crystal structure, critical temperature (Tc) and excess conductivity of Bi-Pb-Sr-Ca-Cu-O (BPSCCO) system. Bulk BPSCCO samples were fabricated by the solid-state reaction method. Four different temperatures of 835 °C, 840 °C, 845 °C, and 850 °C were applied to sinter four different samples. The crystal structure of the samples was investigated through X-ray diffraction measurements (XRD) and scanning electron microscopy (SEM). Superconductivity of the samples was analyzed by the temperature-dependent resistivity measurement. The experimental results showed the existence of both Bi-2223 and Bi-2212 phases in all samples. Quantitatively, the volume fraction of the Bi-2223 phase was found to increase from 53.56% to 75.97%, and the average grain size of Bi-2223 phase was observed to enlarge from 57.95 nm to 86.50 nm as the sintering temperature increased from 835 °C to 850 °C. In addition, the excess conductivity analyses based on the theory of Aslamazov - Larkin (AL) and Lawrence - Doniach (LD) showed decreases in the coherence lengths (ξc(0)) from 1.957 Å to 1.565 Å and the effective inter-layering spacing (d) from 79.7 Å to 64.5 Å. Meanwhile, the interlayer coupling strength (J) between two CuO2 planes was estimated to increase from 0.00083 to 0.00137. These results might be evidence to conclude that the increasing of the sintering temperature obviously improves the superconductivity in the BPSCCO system.
 

Comparative analysis of the temperature dependences of the resistivity, pseudogap, and thermoelectric power in polycrystals YBa2Cu3O7–δ with a decrease in the density of charge carriers

Comparative analysis of the temperature dependences of resistivity ρ(T), excess conductivity σ′(T), pseudogap (PG) Δ*(T), and thermoelectric power S(T), measured on textured YBa2Cu3O7–δ (YBCO) polycrystals with different charge carrier density nf, depending on the level of doping with oxygen, modified by annealing, has been carried out. It is shown that for an optimally doped (OD) sample with Tc = 90 K (sample S1), σ′(T) near Tc is well described by the Aslamazov–Larkin (AL−3D) and Maki–Thompson (MT-2D) fluctuation theories, demonstrating 3D–2D crossover with increasing temperature. The crossover temperature T0 was used to determine the coherence length along the с axis, ξс(0). With a decrease in nf (samples S2 with Tc = 84 K and S3 with Tc = 80 K), the MT contribution is suppressed, and the σ′(T) dependence obeys the Lawrence–Doniach model, which is typical for samples with defects. The dependence Δ*(T) obtained for S1 has a form typical for OD single crystals of YBCO with a maximum at Tpair ∼114 K and a linear section descending to T01 ∼94 K, which limits the region of superconducting fluctuations above Tc. As nf decreases, the shape of Δ*(T) noticeably changes and becomes typical for YBCO films with a symmetric maximum at Tpair, which is the BEC–BCS transition temperature in high-Tc superconductors. As nf decreases, the slope S(T) changes from positive to negative, demonstrating a feature at the PG opening temperature T*. Accordingly, the dependence of S(T)/T on log T changes from linear to nonlinear, which indicates a change in the nature of interactions in the YBCO electronic subsystem with decreasing nf, since S/T ∼1/nf.

Comparative study of structural and fluctuation-induced conductivity in YBa2Cu3Oy added with ZnO and Zn0.95Mn0.05O nanoparticles and nanobelts

In this report, we present the effect of nano-ZnO and nano-Zn0.95Mn0.05O nanoparticles (NPs) and nanobelts (NBs) in polycrystalline superconducting samples of YBa2Cu3Oy (for brevity Y-123). The samples were synthesized using the solid-state reaction. Structural results analyzed via X-ray diffraction showed a similar behavior in all samples while the c parameter increased in the case of samples doped with nanobelts. Measurements of the electrical resistivity’s dependence on temperature revealed that the depression in the superconducting temperature is more pronounced in samples doped with nanoparticles compared to those doped with nanobelts. The excess conductivity in the mean-field region was analyzed using the Aslamazov–Larkin and Lawrence–Doniach models. The effective layer thickness, the zero-temperature coherence length, the wire cross-sectional area, the critical magnetic fields, and the critical current density were also calculated. The Zn0.95Mn0.05O nanobelts are more suitable for enhancing the flux pinning properties of YBa2Cu3Oy.

Fluctuation Conductivity in MOD-Derived YBCO Thin Films

Normal-state properties of some epitaxial YBa2Cu3O7-δ thin films which were derived from the metal-organic deposition route were studied through the context of Aslamazov and Larkin theory of fluctuation conductivity. Six samples with various superconducting properties were selected for this purpose. Resistivity vs. temperature analysis showed that the general normal-state behavior of the samples can be described by 3D, 2D, and 1D Aslamazov and Larkin model of fluctuation conductivity. Samples with the higher superconducting transition temperatures showed the higher Josephson interlayer coupling. Moreover, a linear behavior has been found between Josephson interlayer coupling constant and critical current density. In addition, fitting excess conductivity with Lawrence-Doniach (LD) and Maki-Thompson (MT) models revealed that the LD term dominates in 3D region near the superconducting transition. However, the MT term gains an important role in 2D region far away superconducting transition.

Intersection point of the transport energy curves in type-II layered superconductors with strong thermal fluctuations

The thermal fluctuations contribution to the transport energy of type-II layered superconductors is investigated in the framework of the Lawrence–Doniach model. It was discovered that temperature dependence of the magnetization and the magnetoconductivity of high-temperature cuprate superconductors exhibits an intersection point at a temperature slightly below Tc in a wide range of fields. We detect a similar intersection point of the transport energy curves at temperature just below Tc in a wide range of fields. Strong thermal fluctuations with interactions treated by a self-consistent theory is used to explain the intersection point. Our results include all higher Landau levels. We show that the two-to three-dimensional crossover is the key for the existence of intersection point.

Phase Formation and Conductivity Fluctuation Investigation in Nanoparticle SnO2-Added Y3Ba5Cu8O18 ± δ Polycrystalline Superconductor

The influence of 0, 0.20, 0.40, 0.50, and 0.60 wt % nano-sized tin oxide (SnO2) particles on electrical conductivity fluctuation in normal and superconducting state of the Y3Ba5Cu8O18 ± δ (denoted as Y‑358) polycrystalline samples is studied. Phase formation and microstructures have been systematically examined. By increasing the content of SnO2 in YBCO matrix, X-ray diffraction technique showed slight variation in lattice parameters and overall reduction in the orthorhombicity. Scanning electron microscopy observations and the crystallite size calculation also revealed that the grain size and the average crystallite size decreased compared to the SnO2-free sample. Aslamazov–Larkin and Lawrence–Doniach prototypes were used to analyze conductivity fluctuations based on the electrical resistivity ρ(T) measurements. Superconducting transition temperatures TC and TLD have been reported. The influence of SnO2 addition on the superconducting properties indicates that with the addition of SnO2 nanoparticles into Y-358 compound, some parameters values such as zero-resistance critical temperature TC zero, coherence distance alongside the c axis at 0 K ξc(0), and super-layer length d decrease in total, while anisotropy γ, critical magnetic fields Bc1(0), Bc2(0), and critical current density Jc(0) increase in SnO2-added Y-358 specimens compared to the pure one. The reasons corresponding to these scenarios are discussed in details.

Large enhancement of conductivity in a strongly layered type-II superconductor with an artificial pinning array

Abstract We use the time-dependent Ginzburg–Landau equation to describe a type-II superconductor in a magnetic field in the presence of both strong thermal fluctuations and an artificial pinning array. Thermal fluctuations are represented by the Langevin white noise. The layered structure of the superconductor is taken into accounted with the Lawrence–Doniach model. The self-consistent Gaussian approximation is used to treat the nonlinear interaction term in the time-dependent Ginzburg–Landau equation. In the case of the $\delta $-function model for the pinning centers and the matching field, analytic expressions for the fluctuation electrical and thermoelectric conductivity are obtained. It is found that the fluctuations in electrical and thermoelectric conductivities increase with increasing pinning strength, and when the pinning strength comes near a critical value, the fluctuation conductivity is greatly enhanced. Our result shows that if a pinning array is added to a mixed state superconductor, the original properties of the superconductor are recovered. Physically, in the presence of thermal fluctuations, when the energy scale of the vortex lattice shear fluctuations becomes comparable to the pinning energy scale there is a large enhancement of the fluctuation conductivity in the presence of pinning.

Determination of critical superconducting parameters based on the study of the magnetization fluctuations for RE3Ba5Cu8O18-δ (RE= Sm, Eu, Gd, Dy and Ho) ceramic superconductor system

In this paper, we report the production of cuprate-like superconductor RE3Ba5Cu8O18-δ (RE-358, RE = Dy, Gd, Sm, Eu and Ho) by using the solid reaction method. By means of vibrating sample magnetometry technique (VSM), magnetization curves as a function of temperature were acquired in a Zero Field Cooled/Field Cooled (ZFC/FC) mode. Critical temperature Tc and irreversibility temperature Tirr values were obtained from magnetization curves. The irreversibility line was constructed with Tirr data, it showed an Almeida-Thouless dominant trend for low magnetic fields and Gabay-Toulose behavior for high magnetic fields. Thermodynamic fluctuations were analyzed on magnetic measurements using Bulavskii, Ledvij y Kogan model (BKL) that analyze the vortex fluctuations on Lawrence-Doniach (LD) framework. With this model, penetration length parameters λab and ab-plane coherence length ξab band c-direction ξc was obtained. Crossing point coordinates of the excess magnetization vs. temperature curves for different applied magnetic field amplitudes T* and ΔMab* were determined. Weak magnetic fields were fitted at Δχ/T limit as a function of reduced temperature ε (≥10−2). This procedure allowed us to obtain the mid-field transition temperature value Tc0. Likewise, As (Schmidt diamagnetism) and BLD (LD parameter) constants were found for each of the RE-358 system samples. This showed that through thermodynamic fluctuations analysis, RE-358 system has an excellent bidimensional behavior (2D) and it is strongly anisotropic.

Excess conductivity investigations of WO3 nanowires added to YBa2Cu3O7-d superconductor

Series of YBa2Cu3O7-d + x wt% WO3 nanowire mixtures where x = 0.0–2.0 wt% were prepared via solid-state reaction method. X-ray diffraction (XRD) patterns show the unaffected orthorhombic structure in various composites. Scanning electron microscopy (SEM) micrographs show the increase in grains size and the filling of voids between grains by WO3 nanowires. The superconducting transition temperatures deduced from electrical resistivity versus temperature (ρ(T)) measurements are almost unchanged by lower WO3 nanowires addition (i.e., x 0.5 wt%). The analysis of excess conductivity fluctuation (∆σ) by means of Aslamazov–Larkin (AL) and Lawrence–Doniach (LD) approaches was investigated. Dimensional fluctuations, coherence lengths, effective layer thickness, zero temperature lower and upper critical magnetic fields (Bc1 (0) and Bc2 (0)), and critical current density at temperature T = 0 K (Jc(0)) were extracted and discussed in relation with the structure and morphology. Improvements in Bc1 (0), Bc2 (0), and Jc(0)) were noticed for samples added with lower WO3 nanowires content, particularly for x = 0.1 wt% composite sample.

Дифференциальная термоЭДС углеродных нанотрубок типа "zigzag" во внешнем электрическом поле

The influence of (0.00, 0.20, 0.40, 0.50, and 0.60wt%) nano-sized tin oxide (SnO2) particles on electrical conductivity fluctuation in normal and superconducting state of the Y3Ba5Cu8O18±δ (denoted as Y-358) polycrystalline samples is studied. Phase formation and microstructures have been systematically examined. By increasing the content of SnO2 in YBCO matrix, X-ray diffraction technique showed slightly variation in lattice parameters and overall reduction in the orthorhombicity. Scanning electron microscopy observations and the crystallite size calculation also revealed that the grain size and the average crystallite size decreased compared to the SnO2 free sample. Aslamazov–Larkin and Lawrence–Doniach prototypes were performed to analyse conductivity fluctuations based on the electrical resistivity ρ(T) measurements. Superconducting transition temperatures Tc and TLD have been reported. The influence of SnO2 addition on the superconducting properties indicates that with the addition of SnO2 nanoparticles into Y-358 compound, some parameters values such as zero-resistance critical temperature Tc zero, coherence distance alongside the c axis at 0K ξc(0), and super-layer length d decrease in total, while anisotropy γ, critical magnetic fields Bc1(0), Bc2(0), and critical current density Jc(0) increase in SnO2-added Y-358 specimens compared to the pure one. The reasons corresponding to these scenarios are discussed in details.

Electrical properties and fluctuation induced conductivity studies of Bi-based superconductors added by CuS nanoparticles synthesized through the aqueous route

The effect of copper sulfide (CuS) nanoparticles synthesized by aqueous route on the electrical transport and on the fluctuation induced conductivity of polycrystalline (Bi,Pb)2Sr2Ca2Cu3Oy (denoted Bi-2223) was reported. The global critical current densities versus temperature, Jct(T), at self and applied magnetic field was analyzed within the collective pinning model. The electrical resistivity versus temperature, ρ(T), above the mean-field temperature Tc was analyzed using Aslamazov-Larkin (AL) and Lawrence-Doniach (LD) models. Different fluctuation regimes indicated by short-wave region (SWR), three-dimensional (3D), two-dimensional (2D), one-dimensional (1D), and critical region (CR) fluctuations were identified. The zero-temperature coherence length, the effective layer thickness, the critical magnetic fields, and the critical current densities are determined. It was found that samples sintered with an additional amount of CuS nanoparticles (< 0.4 wt%) exhibit higher upper critical magnetic fields and critical current densities compared to the pure one and the highest values of these parameters are obtained in the 0.2 wt% CuS added sample. Consequently, the addition of CuS nanoparticles could introduce strong pinning centers that contribute to the decrease of magnetic vortex motion which enhances the flux pinning capacities and the transport abilities inside the Bi-2223 system.